Monday, November 24, 2014

Wild Black Yonder


Arthur Darris of Chicago, IL emailed me with the following question; upon discussion over the past couple days, he said I could use our [slightly paraphrased] conversation as a blog post. Regarding the mention of Radio Telescope technology on my last Trivia Series, Arthur asks:

There is something I have wondered about as we search for radio signals from space hoping to pick up signs of life. Why radio? Is it because that is what we use? I thought I read that our own signals aren't reaching deep space as once thought... don't they degrade as they travel? Maybe ETs don't want to interfere with our natural development so they ensure we do NOT detect them. Maybe they communicate in ways we cannot detect yet? But I never hear anyone say this when they talk about SETI. If we learned how to travel beyond our solar system, wouldn't we also need a faster way to communicate?

Electromagnetic Spectrum
That tiny rainbow band is all humans can see!

Why radio waves? That is a long and monumental answer, packed with delightfully nerdy details, but the short version is: because radio waves are THERE.

Radio waves are everywhere. They are "universal" in the literal sense of the word! Truly, humans did not invent and emit them to keep up with Top 40 Hits. ;)

Electromagnetic radiation transports energy at the speed of light. Radio waves are just one form; other forms include visible light [to human eyes], X-rays, infrared, microwaves, etc.  Electromagnetic radiation is widely detected, easily received, can be easily generated artificially, and lasts across vast distances… even through massive dust clouds.

Frequency Allocation
Use of the radio spectrum is regulated by
governments through frequency allocation

Any other techie planet will discover those waves, as we did, and they'll find that tons of things in the cosmos emit all sorts of waves.

Once the wave  properties are examined, any scientific observers would notice oscillation, which determines frequencies. The downside is the enormous spectrum of possible frequencies; they won't know ours, and we won't know theirs. And yes, they degrade over distance, since they are forms of energy. Everything degrades over time and distance.

So hey, let's point a big dish at the sky to collect radiation in high concentrations and amplify frequencies! Or how about a whole pack of dishes? The more dishes you have working together to provide focus, the more accurately faraway sources of various signals can be pinpointed and examined for location, distance, motion, etc. Hence, arrays.

Electromagnetic Radiation Spectrum
Same Galaxy, Different Wavelengths

I had a college professor who was very down on arraying, or as he called it "desperately listening to invisibility" LOL, but I don't think it's so far-fetched. Neither does SETI, and hopefully SETI will survive. We could get lucky. In fact, many scientists believe that radio signals will be our ultimate communication, and not space travel . Our chances of finding other civilizations via Star Trekian propulsion is not currently possible, given time and distances between possible habitable planets – even if we detect them from a vast distance.

Interestingly, according to one sample, 1 in 5 people believe aliens already live among us... disguised! I tend to think of this as the "badly informed by Hollywood" tinfoil hat crowd, but who knows – the joke may one day be all on us skeptics.

E.T. Extra Terrestrial
If you know what this is... you're old.

Sorry. I meant that to be brief. Or maybe it was. I nut-shelled. But you can also find huge amounts of interesting data if you Google "Radio Astronomy."

Monday, November 17, 2014

Telescopin' Trivia


Peak Meteor Shower time! Hope everyone is enjoying the Leonids! And what better time to appreciate our telescopes-- which often translates into coveting a newer, better, bigger one.

Conventional history records that German-born Hans Lippershey invented the telescope in 1608, but legend has it that the device was actually invented years earlier by children playing with lenses in his shop where he created eye-spectacles. Other stories say his apprentice first hit upon the idea of doubling refracting lenses. Nonetheless, Lunar Crater Lippershey is named after him, and not the help.

Coastal merchants were the first competitive consumers of early telescopes, using them to spot approaching trade ships; certainly sailors also found them handy when scanning for land masses -- but Galileo Galilei was the first to use one for astronomy. Turning the telescope heavenward, he found the Galilean moons, noted the phases of planet Venus and also analyzed and described sun spots.

Most of the world's largest optical telescopes (listed by aperture) are now built in remote areas, or atop remote peaks, so as to operational in clean, thin air.

For over 70 years, the largest telescope in the world was located at Birr Castle in Ireland. The 40-ton reflecting telescope with a 3-ton mirror, built by the Earl of Rosse in 1845, was nicknamed the “Leviathan of Parsonstown”. Suspended between two giant stone walls, the telescope offered views of Jupiter and one was later used to observe nebulae.

Leviathan of Parsonstown

Today, the largest telescope in the world is the Gran Telescopio Canarias (GTC) at the Observatorio del Roque de los Muchachos in La Palma, Canary Islands (Spain).

From 1993 (when fitted with corrective lenses after deployment) to the present, the Hubble Space Telescope has been the source of more than 25% of all published astronomy research papers. Funny how you never hear anyone gripe anymore that it was 7 years late and over-budget.

Radio Telescopes in northern California
Radio Telescopes that pick up celestial radio waves instead of light, being all the modern rage, now number over 100 and span the globe. Singular dishes and arrays can be found in both Americas, Europe, Asia, Australia, New Zealand, Africa and Antarctica. There have even been two in space!

The majority of professional astronomers don't even look through eye-pieces anymore. Telescopes are largely operated remotely with computers! Even casual computer users can access robotic observatories from home now. Want to try an internet-based telescope? Go to Seeing In The Dark at Cornell University's Astronomy Department.

Thursday, November 6, 2014

Happy Carl Sagan Day 2014!


Happy, happy Sixth Annual Carl Sagan Day!

This year's theme is,unshockingly, "COSMOS: A Spacetime Odyssey," and once again, Florida's Broward College has planned awesome lectures, planetarium shows, children's activities, educator workshops, COSMOS episodes, telescope instruction, and star-gazing.  The celebration includes a fundraiser dinner to honor what would have been Sagan's 80th birthday.

Most folks recognize Carl from COSMOS in the 1980s, the most widely watched program in PBS history! No surprise, the reboot this past year with Neil deGasse Tyson was also incredibly popular! I've blogged numerous times about my idolization of his highly-quotable written material, my great love for his part in the Voyager Golden Records and their longevity, and last year, I was so pleased to visit a major bucket list item, the Carl Sagan Planet Walk scale solar system!

Carl taught at Cornell and Harvard universities, and worked at the Smithsonian Astrophysical Observatory. Other titles included technology officer of the Icarus planetary research journal, Planetary Science Chair at the Astronomical Society, Astronomy Chairman at the Advancement of Science Association, and Co-Founder of the Planetary Society, the Earth's largest space-interest group.

Carl Sagan passed away in December 1996 at the age of 62, and was buried in New York (Lakeview Cemetery, Ithaca) right beside his parents.

An astronomer, philosopher, professor and NASA consultant, Carl Sagan won 30 public awards, published over 600 scientific articles and authored or co-authored 20 books. I’ll never weary of recommending Pale Blue Dot to anyone who will listen!  The unmanned Mars Pathfinder spacecraft was renamed the Carl Sagan Memorial Station in 1997. Asteroid 2709 Sagan is also named in his honor.

Sagan was instrumental in the early Mariner missions to Venus, determined landing sites on Mars for the Viking Lander probes, and also assembled the first physical messages sent into space.  He was instrumental in establishing the Search for Extraterrestrial Intelligence(SETI), urging the use of radio telescopes to detect signals from other intelligent life. Along with Frank Drake, he also composed the Arecibo message, beamed once into space in 1974.

He's one of those people who makes you scratch your head and think, "What the heck have I been DOING with my time?!"

Carl had the ability to make space "knowable" to audiences of all ages. He was known for popularizing  science in a way that inspired people to understand both our insignificance in the larger universe, but also, paradoxically, the absolutely precious nature of our enormously unlikely existence.

Follow me on Twitter today for #TriviaThursday, all day today, which is all about Carl Sagan's life, works, activism, and scientific accomplisments!  Speaking for space geeks everywhere... thanks a billion, Carl.